<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>css-notes</title>
  <style type="text/css">
    table, td, th {
      border: 1px solid green;
    }
    th {
      background-color: green;
      color: white;
    }
  </style>
</head>
<body>
<table>
  <tr>
    <th>Firstname</th>
    <th>Lastname</th>
  </tr>
  <tr>
    <td>Bill</td>
    <td>Gates</td>
  </tr>
  <tr>
    <td>Steven</td>
    <td>Jobs</td>
  </tr>
</table>
<p><b>注释：</b>如果没有规定 !DOCTYPE，border-collapse 属性可能会引起意想不到的错误。</p>
</body>
</html>
